Sweetgrass, a traditional herbal remedy, was used by Native Americans as an insect repellent. So, chemists extracted essential oils from the plant and demonstrated that they were about as effective as DEET at keeping mosquitoes away.

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Sweetgrass, a traditional herbal remedy, was used by Native Americans as an insect repellent. So, chemists extracted essential oils from the plant and demonstrated that they were about as effective as DEET at keeping mosquitoes away.